Combined check valve and strainer



May 27, 1952 T- c. ODONNELL ,5

COMBINED CHECK VALVE AND ISTRAINER Filed April 17, 1950 INVENTOR 40 YZ'RRZ/YCE' (I 0100mm Patented May 27, 1952 Terrence '-C. *ODonnell, West Springfield, Mass "akssig'nor 150 -Gilber-I;- & Barker Manufacturing Company, West Sprintion- Massachusetts gfleld, Mass, 2. corpora.-

liliplic'ation Apr-i117, 1950, Serial No. 156324 3 Clainis. (Cl. 210e-166l 'This invention relates to a combined valve and strainer unit for use inpumps; asfo'rex'ample; on the suction side of "a-pump forthe purposes of preventing back flow of liquid and straining the liquid before it enters'the pump.

'The'invention'has for an object'the'provision of a unit'of the typeand for the purpose-described, whichmay be easily removed from the pump wl'ie'n' 'ne'zc'essary and replaced by a similar new-unit.

Theinvention also has-for an obje'ct'the pro vision of a replacement unit for pumps embodying a =check-valve and strainer and also, if desired, a relief valve for relieving excess presure 'from expansion of the liquid.

'The invention has for another object-the provision of a combined valve and strainer unit having generally simplified'a'nd improved construction.

lhe'invention will be disclosed with reference' to the accompanying drawings, in which:

-Fi'g..-1-is an elevational view of a'pump with partsinsection and showing the combined'valve and strainer' u'nit applied thereto;

Fig. 2 is a seictional'elevational view drawn, to a larger sca'le of the valveandstrainer unit;

Fig.3 is; a sectionalplan view taken on the line 3-'-3 of Fig.2;

Fig. 4 is a bottom plan view of the unit;

Fig. 5 is an enlarged, fragmentary sectional elevational view showing in detail the constructi'on ofthe checkvalve with arelief or back-flow valve therein; and

Fig. 6- is a fragmentary sectional elevational view showing another form of valve.

Referring to these drawings and first toFig. Zthereofithe device includes a frame which consists-of an annular ring I, a disc-likememberl, coaxial withland axially-spaced from ring land a. plurality of bars 3 (two as shown), which rigidly connectthe ring and member near their outerperipheral portions. A bearing'd, forming-a valvestemguide, is located coaxially of the Adapting H. surround ingstem I0 -acts between :2 the lower end face orguide-d and a--suitableabutment I2 onthe-"stem *toholdthe valve wtoiits seat.

The ring I-and member 2havecoaicialcylindrical portions I 3 and I4, respectively, forming seats "to 'receive and closely "fit the ends f'of *a tubular screen l5. One "end of"'this"screen abuts an annular shoulder I6 on ring "I. "Asnap'jrin'g II, mounted'in'a groove in "the'surface"f4 of member 2, engages theopp'osite end "oiscreen "f5 and holds its against any substantial axial "displacement. The described ring "liprovides de-. sirable support for screen I5 at aloca.tioniinterme'diate its end supports.

/ The ring Ihasan external cylindrical surface I8 which. is "adapted, as shown inf'Figfl, .to fitlin the cylindrical opening in an inner or partition wall of a pump,--such as the opening I9 in wall 20. This surface I8 has thereimacircumferentialgroove to receive asuitablepackingring 2|, whichtightly presses against theperipheralwall. of opening I9 to seal the-joint between-it and the-surface I8. The ringl further-has an an nular shoulder 22, which projects beyond the surface I8 and is'adapted to tightlyrseat-against the outer face 23 of' Wall-2D. The outer end of surface I8 is preferably bevelled as at I8.

The, member 2 has an annular, tubular part 224' projecting awayfrom-the screen I15. :This;.cylindrical outer-periphery of part. 24 'has,2intermediate its ends, an encompassing ring-like projection .2501? semi-circular cross-sectional.Ishape. This "projection is adapted to" flt' with line eam tact only-in a cylindrical opening 26 i-n' aIcap nut 21. The latter: is exteriorly threaded to "screw into "an interiorly "threaded opening .28 riin an outer-wall 29 ofthe pumn closingsuch opening.

Within the nut is a coil sprin'g :30 which extends into the opening in part Mandi-pressesupwardly on the member 2 in order to force the shoulder 22 against 'the fa'ce 23 .of' wa1l'2'0. Projecting centrally from member 2 i into the tubular 1 part 24 1s aprojection- 3 I whichfnas-two parallelisides.

(Fig; 4)- which may be graspedb'y a' pairof pliers for extraction" purposes as' w'ill later' appear' and is wide enough to fit' into' spring' 3'0 and-roughly center the same.

There is shown in Fig. 1 a rotary pump "P which has an inlet'chamber 32,: adapted ior'connection to the suction -pipe 33 "and a second chamber 34-having as its outlet the inletaport 35 of the pump chamber. The screen I 5 spans the inlet F chamber 32. Liquid 1 from "i'the 'latter passes radially through the Screen and tlience plied to opposite faces thereof. One end of this stud has a hexagonal head 40 and the other end is threaded to receive a nut 4| by means of which the member 9 and its washers 38 and 39 are clamped between the head 40 and nut. The stud 31 has a coaxial and internally-threaded opening 42 therein, extending from its outer end inwardly toward but terminating short of head 40. A small passage 43 extends through head 40, obliquely to the axis of stem 10, and connects the inner end of opening 42 to the space below head 4%. The relief valve is mounted in a hollow stud 44, which is threaded into hole 42 and which has at its outer end a hexagonal head 45 to seat against the outer end of stud 31. A rubber-like O-ring packing 46 seals the joint between the two hollow studs. The valve 36 has a rubber-like O-ring 4? to engage a seat 48 on the inner end of stud 4% and a stem 49 which extends outwardly through the opening in stud 44 and has a threaded end to receive a nut 50. The opening in bushing 44 has, at a location intermediate its ends, a shoulder 52. A conical coil spring 53 acts between this shoulder and nut 5!] to hold valve 35 on its seat 48. On an excessive rise in pressure in chamber 34 valve 35 will open and allow liquid to flow from opening 5| into opening 42 and passage 42 into chamber 32 of the pump.

If the relief valve 36 is not needed, the stud 44, which carries it, can be removed, and the opening 42 closed at its outer end by a suitable plug. Or the construction can be as shown in Fig. 6, where a smaller and solid stud 53' passes through the valve 9 and its washers 38 and 39 and carries a nut 54 for clamping the valve and its washers against a head 55 on the stud.

In applying the unit to a pump, the spring 36 is placed in cap nut 2'! and the lower end of the tubular extension 24 of the frame is pushed into the opening 26 in the nut, the spring being centered by the projection 3i. The rib will fit the opening near the upper end thereof so that the valve and strainer unit, the nut and spring will be held together. The unit is thrust inwardly through hole 28 and the forward beveled edge of ring I serves as a pilot to facilitate the entrance of ring I into hole l9. The nut 27 will be turned to thrust the screen and valve unit upwardly until the part 18 is in place in hole l9 and the shoulder 22 abuts the face 23 of partition 20. The nut then turns without turning the valve and strainer unit because there is only the contact along rib 25 between the member 24 and nut. Thus, the nut can be tightened to compress spring Stand finally seat on the outer wall 29 without rotating the valve and a strainer unit and causing Wear on the packing 2!.

Whenever the unit needs replacing, the nut is unscrewed and the unit is drawn out of the pump. The unit will usually not follow the nut, so that the nut will be removed with spring leaving the unit in place. However, the flat-sided projection 31 is exposed and may be grasped by a pair of pliers to pull out the unit. A new unit'is placed in the nut and assembled in the pump as above described.

What is claimed is:

1. A combined valve and strainer unit, comprising, a frame consisting of an annular ring having at one end thereof a valve seat surrounding the opening therethrough, a coaxial disclike member axially spaced'from said ring, a plurality of bars rigidly interconnecting the ring and member at angularly spaced locations about their outer peripheries, a valve-stem guide located adjacent the other end of said ring in coaxial relation therewith and between the valve seat and member, and spider arms rigidly interconnecting the guide and bars, said ring having two exterior cylindrical portions separated by a flange having axially-spaced annular shoulders located in planes normal to the axis of the ring, one said portion forming a plug adapted to fit in an opening and having a circumferential groove, a packing ring in said groove, the other cylindrical portion forming a screen seat, said member having an exterior cylindrical screen seat portion, a screen mounted at its ends one in each of said screen seats and spanning the space between the ring and member, a poppet valve engaging the valve seat on said ring and having its stem slidably mounted in said guide, an abutment on said stem between the guide and member, and a spring on the stem acting between one end face of said guide and said abutment to hold the valve to its seat.

2. A combined check-valve relief-valve and strainer unit, comprising, a frame consisting of an annular ring having at one end thereof a valve seat surrounding the openingtherethrough, a coaxial disc-like member axially spaced from said ring, a plurality of bars rigidly interconnecting the ring and member at angularly spaced locations about their outer peripheries, a valvelstem guide located adjacent the other end of said ring in coaxial relation therewith, and spider arms rigidly interconnecting the guide and bars, said ring having two exterior cylindrical portions separated by a flange having axially-spaced annular shoulders located in planes normal to the axis of the ring, one said portion forming a plug adapted to fit in an opening and having a circumferential groove, a packing ring in said groove, the other cylindrical portion forming a screen seat, said member having an exterior cylindrical screen seat portion, a screen mounted at its ends one in each of said screnseats and spanning the space between the ring and member, a poppet valve engaging the valve seat on said ring and having its stem slidably mounted in said guide, an abutment on said stem, a spring on the stem acting between one end face of said guide and said abutment to hold the valve to its seat, said valve having therethrough a passage interconnecting opposite faces thereof, a relief valve mounted in the first-named valve and normally closing such passage, and a spring tending to hold the relief valve closed and yieldable to enable it to open in a direction opposite to that in which the first-named valve opens.

3. The combination in a pump casing, wherein two chambers are separated by an internal partition having a cylindrical opening therethrough, and an outer wall forms a wall of one such chamber and has therethrough a screw threaded opening coaxial with the first-named opening, acombined check -valve and strainer unit spanning the last-named chamber and supported from said wall and partition, said unit including a frame consisting of an annular ring having an outer peripheral surface to fit the first-named opening and a flange projecting beyond such surface to seat against said partition, a coaxial disc-like member, and at least one bar rigidly interconnecting the ring and member near their outer peripheral portions, a nut threaded into and closing the opening in said outer wall, a spring acting between the inner face of the nut and the adjacent end face of said member to press the frame toward the partition and seat said flange against said partition, said ring and member having coaxial cylindrical seats one on each, a screen having its ends mounted one on each said seat and spanning the space between the ring and 1 TERRENCE C. ODONNELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,847,068 Campbell Mar. 1, 1932 2,134,413 Munoz Oct. 25, 1938 2,352,315 Gilbert June 27, 1944 2,512,877 Rike June 27, 1950 

